A California teenager who is allegedly behind a flurry of swatting incidents across the country targeting schools and the homes of FBI agents has been arrested in connection with a swatting attempt at a Florida mosque last year, according to court documents filed by state prosecutors.

Alan Winston Filion, 17, was arrested last month at his home in Lancaster, California, and extradited to Florida on Tuesday, court documents say. He was charged as an adult on four felonies, including charges related to false reporting that triggered law enforcement response. 

Filion entered a not guilty plea to the charges. He is being held without bail at the John E. Polk Correctional Facility.

Filion is allegedly behind hundreds of swatting incidents across the country targeting high schools, historical black colleges, and the homes of FBI agents, according to a motion filed by the government to secure Filion’s detention in the Mosque case.

In May of last year, deputies from the Seminole County law enforcement responded to a caller who said he was armed with a handgun and explosives and was entering the Masjid Al Hayy Mosque in Sanford, Florida, to carry out a mass shooting, according to county records.

Upon their arrival, officers said they saw a woman and her two children at the building’s entrance and identified the call as a hoax after speaking with them, records show.

According to newly-unsealed court documents obtained by NBC News, the Seminole County Sheriff’s Office and the FBI have tracked Filion’s posts on Telegram offering up his swatting services, as well as recordings of swatting calls. They allege he was responsible for hundreds of swatting incidents, including in Louisiana, Maryland, Oklahoma, Pennsylvania, Texas, and Washington. The swatting attempts allegedly have included bomb threats at high schools and a nongovernmental organization that researches extremism.

NBC News reported last year on the FBI and its online database for swatting tracking and prevention that is housed at the FBI Criminal Justice Information Services Division in West Virginia. According to the arrest warrant affidavit, following that report, Filion posted a diagram online threatening to call in bomb threats to that FBI facility in West Virginia and to swat Supreme Court justices and senators. 

Shortly thereafter, a 911 caller claimed he had stashed three dozen pipe bombs around the FBI facility that would detonate in 30 minutes, according to the affidavit. No explosives were found.

In the days that followed, a series of top FBI special agents at field offices in Pittsburgh, Oklahoma City and San Antonio, and the head of the Criminal Justice Information Services Division in Washington, D.C., were all targeted by swatting calls at their homes.

The caller’s voice in the mosque incident matched that of the voice heard in the swatting incidents involving FBI personnel, according to the arrest warrant affidavit, which was signed by a detective from the Seminole County Sheriff’s Office and a FBI agent.

The affidavit also said Filion has posted many antisemitic comments online and has an affinity for “The Lord of the Rings.”

They allege he has a pattern of referring to the same weapons, like AR-15s and pipe bombs, in his calls, in addition to making references to Satan. They also allege they have even found posts where Filion has admitted to swatting his own home, documents say.

Filion and his father agreed to an interview, but when agents pressed Filion on whether he swatted his own home, his father became confused and Filion became upset and terminated the interview, court documents say.

An attorney for Filion did not immediately respond to NBC News’ request for comment.

In a statement, Seminole County Sheriff Dennis Lemma referred to the arrest in pointing to the dangers of swatting.

The arrest warrant affidavit notes that swatting, which is the false reporting of a crime in progress to draw law enforcement to a particular location, is dangerous for both the responding officers and victims and can result in the victims’ accidental killings. Swatting also ties up significant law enforcement and emergency resources, the affidavit says.

“Swatting is a perilous and senseless crime, which puts innocent lives in dangerous situations and drains valuable resources,” Lemma said. “Make no mistake, we will continue to work tirelessly in collaboration with our policing partners and the judiciary to apprehend swatting perpetrators.”

Swatting is also difficult to track down, with those making the fraudulent calls often using technology to disguise their voice, caller information and location.

Swatting became a national story after several high-profile incidents involving members of Congress, the White House and former United Nations Ambassador Nikki Haley, who is seeking the Republican nomination for president. Haley was the target of two recent swatting incidents at her home in South Carolina. Both cases were closed with no arrests made.